package MyStudentManager;

import java.util.ArrayList;
import java.util.Scanner;

public class StudentManager {
    public static void main(String[] args) {
        ArrayList<Student> array=new ArrayList<Student>();
        while (true) {
            System.out.println("--------欢迎来到学生管理系统--------");
            System.out.println("1. 添加学生");
            System.out.println("2. 删除学生");
            System.out.println("3. 修改学生");
            System.out.println("4. 查看所有学生");
            System.out.println("5. 退出");
            System.out.println("请输入你的选择");
            Scanner sc = new Scanner(System.in);
            String s = sc.nextLine();
            switch (s) {
                case "1":
                  addStudent(array);
                    break;
                case "2":
                    deleteStudent(array);
                    break;
                case "3":
                  updateStudent(array);
                    break;
                case "4":
                    findallStudent(array);
                    break;
                case "5":
                    System.out.println("谢谢使用");
                    System.exit(0);
            }
        }
    }
    public static void addStudent(ArrayList<Student> array){
        Scanner sc=new Scanner(System.in);
        String sid;
        while(true) {
            System.out.println("请输入学生学号");

            sid = sc.nextLine();
            boolean used = isUsed(array, sid);
            if (used) {
                System.out.println("你输入的学号已被使用");
            } else {
                break;
            }
        }
        System.out.println("请输入学生姓名");
        String name=sc.nextLine();
        System.out.println("请输入学生年龄");
        String age=sc.nextLine();
        System.out.println("请输入学生居住地");
        String address=sc.nextLine();
        Student s=new Student();
        s.setSid(sid);
        s.setName(name);
        s.setAge(age);
        s.setAddress(address);
        array.add(s);
        System.out.println("添加学生成功");

    }
    public static void findallStudent(ArrayList<Student> array){
        if(array.size()==0){
            System.out.println("请先添加学生");
            return;
        }
        System.out.println("学号\t\t\t姓名\t\t年龄\t\t居住地");
        for(int i=0;i<array.size();i++){
            Student student = array.get(i);
            System.out.println(student.getSid()+"\t"+student.getName()+"\t"+student.getAge()+"岁\t"+student.getAddress());
        }
    }
    public static  void deleteStudent(ArrayList<Student> array){
        Scanner sc=new Scanner(System.in);
        System.out.println("请输入你要删除的学生学号");
        String sid=sc.nextLine();
        int index=-1;
        for(int i=0;i<array.size();i++){
            Student s = array.get(i);
            if(s.getSid().equals(sid)){
                index=i;
                break;
            }
        }
        if(index==-1){
            System.out.println("该信息不存在");
        }else{
            array.remove(index);
            System.out.println("删除成功");
        }

    }
    public static void updateStudent(ArrayList<Student> array){
        Scanner sc=new Scanner(System.in);
        int index1=-1;
        System.out.println("请输入你要修改的学生学号");
        String sid=sc.nextLine();
        System.out.println("请输入学生新姓名");
        String name=sc.nextLine();
        System.out.println("请输入学生新年龄");
        String age=sc.nextLine();
        System.out.println("请输入学生新居住地");
        String address=sc.nextLine();
        Student s=new Student();
        s.setSid(sid);
        s.setAge(age);
        s.setName(name);
        s.setAddress(address);
        for(int i=0;i< array.size();i++){
            Student student = array.get(i);
            if(s.getSid().equals(sid)){
               index1=i;
                break;
            }
        }
        if(index1==-1){
            System.out.println("该信息不存在");
        }else{
            array.set(index1,s);
            System.out.println("删除成功");
        }
        }
        public  static boolean isUsed(ArrayList<Student> array,String sid){
        boolean flag=false;
        for(int i=0;i< array.size();i++){
            Student s = array.get(i);
            if(s.getSid().equals(sid)){
                flag=true;
                break;
            }
        }
        return flag;
        }

    }


